In the Galve sub-basin, the sedimentary record of the Upper Hauterivian–Lower Barremian El Castellar Formation is divided into two stages by a marlstone interval with gypsum. Stage 1 shows a great variety of subenvironments and facies (alluvial, palustrine and lacustrine) whereas in stage 2 an extensive, shallow carbonate lake developed. Sedimentation was controlled by a system of south-dipping, ENE–WSW listric normal faults, laterally bounded by NNW–SSE steeper transfer faults. Faults controlled sedimentation from a basin scale (basin margins and main characteristics and evolution of sediments) to a regional and a local scale (thickness and facies distribution of the synrift series as well as the location and evolution of lakes and minor alluvial fans). The changes between stages 1 and 2 are related to the passing from an independent movement of faults to the movement of all the extensional faults as a whole, at a sole detachment level. The interval with gypsum was caused by underground water flow changes associated with the interrelation and connection of the faults in the transition period. These changes have been correlated with the transition from the rift initial stage to the rift climax stage, which took place in the Hauterivian–Barremian transition.

This paper reports on the structural and sedimentary evolution of the middle to late Eocene of the Prepyrenean External Sierras (southern Pyrenees, Spain). The initiation, duration and kinematics of a set of growth structures that developed in a shallow marine depositional setting is documented. The detailed analysis of the syntectonic marine sediments not only confirms the already known east to west progression of deformation, but also reveals the continued growth of the early formed structures as later ones propagate towards the foreland. The sedimentary units coevally deposited with these growth structures are arranged in four depositional sequences. Their boundaries correspond to flooding surfaces which grade basinwards into correlative conformities. They are also indicated by the presence of both angular unconformities and onlap geometries. Each depositional sequence generally consists of two systems tracts. The lower one, or transgressive systems tract, is formed by up to 400 m of azoic marls deposited in outer ramp areas. The upper one, or highstand systems tract, mainly consists of shallow siliciclastic and carbonate facies, up to 200 m thick, deposited in middle to inner ramp areas. These depositional sequences are interpreted to be controlled by regional tectonic pulses. An increase of tectonic activity resulted in the flooding of the basin and in the subsequent deposition of a thick succession of nearly azoic blue marls (i.e. transgressive systems tract). The overlying highstand systems tract developed following periods of diminished tectonism, with the consequent growth and progradation of shallow carbonate platform facies.

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